At 4:23 PM -0500 3/8/03, John Frey wrote:
>Kevin Ayres supports the TIG.
>>Stan Chayka wrote:
>>> The point to consider is that when the white bar is exposed, the light level
>> behind the pluge area is actually higher making the point of extinction that
> > much harder to set.
>........
>>>> I would like to think that if the pluge is used to set the extinction point,
>> it be done without the contamination of the color bars, and, then see if the
>> blacks match better with projection systems.
>>>>Interestingly, I have a couple of PAL generators which have a pluge
>set amidst a largely black field. ..............
>What should we do? Put a pluge in a grey field?
............
Stan, John, et al,
I have heard from reliable sources that when the Pluge was added to
the color bar signal there was a lot of disagreement among the SMPTE
RP committee members of the usefulness of a Pluge added to a bright
signal such as Color Bars due to the exact same reasons being brought
up in this thread. However, the rational forces did not win out in
this case and Pluge added to color bars is now basically not very
useful. The fact that it is in the corner also doesn't help things as
most monitors will have a significant light drop off in the corners
relative to the center. For that reason, home theater calibrators use
pluge signals that are centered on the screen on a black field and
go from top to bottom of the frame. You can see this and many other
well thought out calibration signals on the two most popular DVD's
used for monitor calibration. It might make good sense for post
production and broadcast engineers to borrow some lessons from their
less well paid home theater calibration cousins. I can tell you the
names of these DVDs if you contact me privately.
Disclaimer: I am currently unemployed (hopefully only temporarily) so
I don't take any money from any monitor calibrators or anyone else at
this time.
--
Dave Corbitt
Madison, NJ 07940
email david.corbitt at verizon.net